Bitcoin (BTC) has revolutionized the financial world with its decentralized, secure and transparent nature. Although it was the first cryptocurrency, Ethereum (ETH) pioneered the development of the entire decentralized finance, or DeFi, ecosystem. Now, Bitcoin is following suit, ushering in an era of development within its own ecosystem. As Bitcoin’s popularity surged, so did the challenges related to its scalability and transaction speed. To address these issues, the Bitcoin community has developed various layer-2 blockchains, or L2s, which enhance the network’s efficiency and functionality without altering Bitcoin’s software itself. This article delves into the concept of Bitcoin layer 2s, exploring their classifications, benefits and expected advancements in this sector. By understanding these innovative protocols, users can comprehend how Bitcoin continues to evolve and maintain its relevance in an increasingly competitive digital landscape. In the end, the bitcoin cryptocurrency is the digital gold and the whole economy is being created around it, analogous to gold in the physical world.